CPL dye developed with spiral-shaped twisted oligophenylene
Promising for applications such as circularly polarized organic LED and bioimaging materials


The study was jointly conducted by a research group comprising Yoshitane Imai, associate professor in the Department of Applied Chemistry at Kindai University; Masashi Hasegawa (lecturer), Kenta Sato (graduate student), and Yasuhiro Masaki (professor)-all from the Chemistry Department of the School of Science at Kitasato University; and Tomohiko Nishiuchi, assistant professor of chemistry in the Graduate School of Science at Osaka University.
They took oligophenylene, a substance that has highly luminescent properties, and simply twisted it into a spiral and then formed a ring to produce helical chirality. They were thus able to develop a green fluorescent dye that exhibits circularly polarized luminescence (CPL).
These synthetic molecules have a brilliantly green luminescence and striking CPL thanks to their helical chirality. The researchers found that the luminescence was especially pronounced for polymethyl methacrylate (PMMA) thin film.
These findings indicate the possibility of developing circularly polarized organic EL (electroluminescent) materials using fluorescent dyes that exhibit CPL. They should also help speed up the development of 3D CPL displays.

The October 20, 2020 online edition of Chemistry-A European Journal selected these research results as a "Hot Paper" and featured them on its front cover.